Floating seal rings are used in pumps to control fluid leakage and generally consist of a seal ring that floats freely within a retainer ring and encircles a rotary or reciprocating shaft. The annular clearance between the seal ring and the shaft is relatively small (i.e., in the range of 0.001 to 0.002 inch). Hydrostatic pressure generated in the pump causes the seal ring to center itself on the shaft. When a pump is operating, high fluid pressure will exist at one end of the floating seal ring while low fluid pressure will exist at the other end of the floating seal ring. If the shaft is deflected or becomes misaligned, the seal ring may be moved against the shaft and cease to float freely, thereby resulting in an undesirable situation commonly referred to as "hydraulic lock".
Stationary seal rings have also been used in pumps to control fluid leakage around shafts. These stationary seal rings are fixed in a housing and, therefore, do not float freely. They have included an annular inner surface which is tapered.
The foregoing illustrates limitations known to exist in present floating seal rings. Thus, it is apparent that it would be advantageous to provide an alternative directed to overcoming one or more of the limitations set forth above. Accordingly, a suitable alternative is provided including features more fully disclosed hereinafter.